Steam motor



' CLE. BISHOP STEAM MOTOR 3 Sheets-Sheet l Filed Deo. 16, 1953 Aug. 3, 1937. c. E. BlsHoP 2,088,582

STEAM MOTOR Filed Dec. 1e, 195s 3 sheets-sheet 2V 8 ema/W Z2/:z JM N 3 fw/ggg@ 222e z M mm M Aug. 3, '1937.

` c; E. @SHO-F K 2,088,582

STEAM` MOTOR Filed Dec. [16, 1933 3 Sheets-Sheet 3 u/ r lf/ IIIIIIIIIIIIIIII'A tor of simple, durable and inexpensive construetion for operating on steam or other expansible Patented Aug. 3, 1937 UNI TE D." "STATES PAT ENT FFI CE STEAM' Moron` Carl nimma` Bishop, Carlisle,` Iowa e Application December 16, 1933, Serial No. 702,746

5 claims. (ci. iai-112i e An object of my invention is to provide'a molui'ci pressure. l. e

A further object is to provide a motor especially adapted for high pressure and high temperaturesteam `for automotive use, such `as on e automobiles, tractors, e aeroplanes, motor boats, rail cars andthe like where a considerable amount of power must be generated, but thespace forthe i `motor is limited and it isalso desirableto minimizc the weight of the, motor in the horse-power delivered `by it. n.

A further object is to procure an ultimate. expansion of steam by a novel compounding construction of the motor, yet get extreme` torque or proportion to turning power for starting purposes, especially when the start must be made under loadas` required by many types of automotiveequipment,"

and control of the motor and the vehicle is simultaneously effected `by a [throttle without the use of a clutch or transmission.

A further objectis to providean expansible e uid pressure motor of few parts and from which Still another Objectis tolprovidea compound type of motor in which steam `from a high` pressure cylinder is transferred directly through a short passageway and a valve to a 10W pressure cylinder, the pistons in these cylinders being so connected with the power `shaft that they always reciprocate in opposite directions, thus making it possible to` simultaneously exhaust steam from the high pressure cylinder andintothe low pressure cylinder without any intermediate receiver or the like `as usually associated with compound steam engines and which always present a problem of heat loss and consequently decreased efciency.

Another object is to provide a steam motor :cf

` compound type vin which the parts are all balanced, the cylinders .being arranged radially around a` power shaft and the reciprocating pistons in the high vand low pressure cylinders always reciprocating in opposite directions so as to mini- `mize vibration which has its greatest tendency to occur at high speed of the motor. 55

Anotherobject is to.soiass`ociate the elements Figure. 1 showing an exhaust valve.

sleeve.

of a steam motor together that a turbine-like actionor an action inwhich a smooth evenly applied torque throughout each degree of each entire revolution is producedin rotating the power .Still another object is provide novel details of construction whereby the valve action iscone trolled partly manually and partly automatically.

A ordinary type are concerned;

With these and other objectsin view my invention consists in the construction, arrangement and'combination of the various parts of my 15 device, whereby the objects contemplated are attained, as vhereinafter more fully set forth, point- 8 ed out in my claims, and illustrated in the accompanying'drawings, in which: y

Figure 1 'is an end elevationof a steam motor 20 embodying myinvention. i Figure 2 is a diagrammatic end view of the motor to show the relation of the high and low pressure pistons` to each other and to the power shaft.

Figure 3 is a sectionalview on the line 3-3 of 5 Figure 1, showing an inlet` valve and a transfer valve.

Figure 4 is a sectional view on the line 4 4 oi' Figure 5 is a sectional View on the line Figure 3 showing an inlet valve cam.

Figure 5A is a sectional view similar to Figure 5 showing a modified shape of cam. l .Figure` 6 is a. similar sectional view on the line 4G-ii of `Figure 3showing a lost motion trans- 35 `fer valve cam andan exhaust valve cam.

Figure 7 is a similar sectional -view on the line le-,1. ofFigure 3 showing a lost motion exhaust valve cam. i

, Figure 8 is a sectional view on the line 8-8 of 40 Figure 1. showing the control mechanism for the inlet valve camiandillustrating it in reversing position. 8

Figure 9is a layout view of the inlet valve ,cam

4 i 45 Figure 10 is a similar 'layoutview `showing a 'modified form of cam lobes. e

Figure 11 is a layout view similar to Figure 9 except showing the lobes arranged without axial spacing.

Figure `12 is a sectional view similar to Eigures 3 and 8 showing amodied form o f construction in which `a. cam for the transfer valve and the exhaust valve is connected with the intake valve cam operating means for simultaneous operation therewith.

Figure 13 is a layout view of the modified cam sleeve oi' Figure 12; and

Figure 14 is an enlarged sectional view of a connecting device shown in side elevation in Figure 12.

On the accompanying drawings, I have used the reference numeral III to indicate a power shaft. In the illustration of my invention, I have shown it in the form of a. crank shaft having crank pins I2 and I4.

'Ihe power shaft I8 is joumaled in suitable bearings, preferably of the ball or roller type (illustrated as plain bearings I6 on the drawings) which are supported by a crank case I8.

High pressure cylinders HI, H2, H2 and H4 are arranged radially around vthe power shaft I8 and suitably connected with the crank case I8. Low pressure cylinders LI, L2, L3 and Mare also arranged radially around the power shaft and connected withA the crank case.

On the drawings, I have illustrated four high pressure cylinders and four low pressure cylinders. Any feasible number of them may be provided, however, the greater the number the smoother and more turbine-like being the action of the motor. The essential consideration is that there shall be one low pressure cylinder for each high pressure cylinder and the two should ,be arranged as closely together as possible to minimize the travel of transferred steam vfrom the high pressure cylinder to the low pressure cylinder.

Reciprocable in each high pressure cylinder is a high pressure piston 20. One of the high pressure pistons has a master connecting rod 22, while each of the other high pressure pistons has a secondary connecting rod 24.

Reciprocable in each low pressure cylinder is a low pressure piston 26. Pivoted to one of these is a master connectingrod 28, while pivoted to each of the others is a secondary connecting rod 28. 'I'he master connecting rods 22 and 28 are rotatable on the crank pins I2 and I4, respectively, while'the secondary connecting rods 24 and 38 are pivoted to the master connecting rods 22 and 28 respectively in the ordinary manner for motors of the radial type. 1

For each high pressure cylinder, I provide an intake valve cylinder 32 having bores 34 and `36.

An inlet port 38 is provided'i'or each valve cyl inder 32. Steam or otherf-expansible fluid presk sure may be controlled by a throttle (not shown) and admitted through a' manifold 40 and inlet v pipes 42 to each port '88.

Each intake valve cylinder 32 is provided with an outlet port 44 which communicates with the adjacent high pressure cylinders. Between the ports 38 and 44 a valve seat 46 is provided. A

valve head 48 is adapted for seating thereagainst,

the valve head and seat being beveled or of Athe poppet type and being normally constrained to engage each other by a spring 50 in a manner common in internalcombustion engine construction. The valve head 48k is attached to a stem 45 extending slidably through the crank case I8 and having on its inner end a roller 41 for coaction with a. valve cam later to bedescribed.

On opposite sides of the valve head 48, I provide sealing pistons 52 and 54 reciprocable within the bores 34 and 36 of the valve cylinder 32.

These, as well as the pistons 20 and 26, are pro- Vvided with suitable piston rings to eliminate the undesired escape of steam.

while the outlet port 44a thereof communicates with the low pressure cylinder. The inlet port 38h of the exhaust valve 48h communicates with the low pressure cylinder, while the outlet port 44h thereof communicates with exhaust piping 56.

For actuating the inlet valve heads 48, I provide an inlet valve cam sleeve 58. The cam sleeve 58 is slidably but non-rotatably mounted with respect to the power shaft Ill, a suitable key 65 being provided for this purpose, or the cam sleeve being splined on the power shaft.I The cam sleeve 58 has circumferentially therearound a forward direction lobe 68 and a rearward direction lobe 62. 'Ihese lobes are shown in laid-out position in Figure 9. Their leading edges are indicated at 60a and 62a, respectively, while their trailing edges are indicated at 68h and 62h, respectively.

It will be noted that the trailing edges slant instead of extending substantially axially of the cam sleeve 58. The purpose of this is to provide intake cam lobes which can be adjusted axially and will vary the cut-off of the steam being adinitted to the high pressure cylinders. For instance, when the cam sleeve 58 is slid to the position of Figure 3, the cut-ofi occurs substantially when the highpressure piston is half way on its down stroke. The down and up strokes of the pistons are merely relativeas the cylinders are arranged radially around the power shaft and throughout the specification and claims down is used to signify motion of the pistons toward the crank shaft, while up is used to signify motion away from the crank shaft.

When the cam sleeve 58 is adjusted toward the right, the cut-off point for the intake valves is delayed, thus admitting steam a longer proportion of the power stroke of the high pressure piston. 'Inversely, when the cam sleeve 58 is slid toward the left, the power stroke is shortened and cut-off may be advanced until a mere puff of steam enters each high pressure cylinder at the beginning of the power stroke of thepiston therein.

For sliding the cam sleeve 58 and thus controlling the cut-oil of the intake valves, I form in the cam sleeve an annular groove 64 and I surround the groove with a collar 66.

Bali bearings 68 are then interposed between the groove and the collar to provide an antifriction connection between the two. 'I'he collar 66 may be slid in any desired manner, a control lever 10 being illustrated for this purpose and having a yoke 12 straddling the col1ar.- The yoke l2 is provided with slots, such as indicated at 14 neutral position preventing the admission of steam to any oi' the high` pressure cylinders and allowing the motor to have a braking eli'ect by reason of vacuousconditionsproducedln the high pressure cylinders when the high pressure pistons move downwardly with the valves 48 and .48a closed. j

A modified construction is Vshown in Figure l`l where thelobelessl lspace 59 is omitted so that thecam sleeve, when adjusted to its central position, opens all the intakevalves 48, lthus permlttingthe full pressure of steam to acton all e the pistons andqulckly stop the motor.

This arrangement of hintake valve actuatorfis desirable where quick stops of 'the `vehicleare required, such as on switching locomotives.

In Figure l0, I have shown forward andreversing cam lobes 6I and having leading edges H ila and 83a similar to those inFig'ure 9 but having stepped trailing edges Sib` and 63h. These give an intake valve cut-oh' in definite vsteps rather than to any `desired degree as when the types of lobes shown used. p l .v With respectto the reversing lobes 62 and 88,

in Figures 9` and"l1 vthe slanting and stepped trailing edges82band 83h can be omitted if desired where it is unnecessary to have any cut-olf when the motor is operatedv reversely due to only infrequent reverse use.

The transfer valves 48a and theexhaust ,valves 48h are open the rst portions only of the down and upstrokes respectively of the low pressure pistons 26. This is for the purpose of clearing the cylinders of steam under pressure, the valves remaining closed the remainderof the strokes for the advantage `of trapping the remainder of the steam and compressing it for cushioning the upstrokes of the high pressure and low pressure pistons, respectively.

This adds to the economy attained by the motor as the steam which provides the cushioning does not have to be provided by opening the intake valve 48 slightly before the high pressure piston reaches top dead center and thus let in live steam which is the usual practice. Thus the steam that is already in the highy pressure cylinder is trapped and is utilizedrather than using newly generated steam from the boiler. For the valves 48a and 48h, I provide a cam sleeve 82- "are shown as having an effective length oi about ninety degrees so that the valves 48a and 48h are open about one-half of theupstrokes `of the pistons 20 and 26. The length of these c ams is `merely arbitrary as in practice it may be found that they should be 'longer or shorter than `illustrated. Also, their length would vary for motors designed for different types of use.

From the foregoing construction, it will be 0bvious that whenever the power shaft 4I0 rotates in a direction opposite from the `direction it previously rotated, the cam lobes 88 and 90 will be shifted with relation to the cam disks 84 and `88 by being held in stationary position `by one or "more of the transfer valve stem rollers 41a and the exhaust valve stem rollers 41h. `Thus valve cams iseftected without any mechanical connectionfto the reversing lever 1l. v

`It possibleA however torso "construct the transfer and exhaust valve cam mechanism that shown such an arrangement'in Figure 12.

A Lcam sleeve 98 isprovided 'which is shiftable bya forked lever 98 connected bya telescoping link `|00 and a spring |02 to thereversing lever 10. ...Cam lobes |04, |06 and |08 are provided and `arranged sothat when the lobe |04 coacts with the roller 4I`a and the lobe |08 coacts with the roller 41h, the valves 48a and 48h are set for rotation in onedirection, while shifting the cam sleeve 88 to its right hand limit of motionin Figure 12 effects reversal. l

In the position just mentioned, the lobe |08 would coact with the roller 41a, while the lobe `|08 would coact with the roller 41h. As clearly shownon the drawings, the lobes |04 and |08 are one-hundred and eighty degrees apart with the respect to the lobe i08.

'I'he telescoping link |00 and the spring ll! serve the purpose of placing the cam sleeve` 88 in a neutral position when the cam sleeve 58 is in neutral position, but places the fcam sleeve SGin either the forward or rearward direction position whenever the sleeve 58 is slightly moved to either side of its neutral position for opera tion ofthe motor either forwardly or reversely.

Thereafter, further swinging of the lever -10 will change the cut-off periods of the `intake valves 48, but the'spring |02 will be either extended or compressed, thus leaving the lobes I08 and |04V or |08 properly alignedfwith the rollers 41a and 41h. Other mechanical mecha--` nism, `of course, can be substituted for that shown to effect manual adjusting of all valves simultaneously.

To minimize vibration at high speed, the pistons 20 and 2B reciprocate in opposite directions and since they have dierent masses because the high pressure cylinder bore is smaller than the low pressure cylinder bore, I preferably balance their weight by making the pistons 20 of heavy metal, such as cast iron or the like, and the pistons` 26 of light metal such as aluminium, linite or the like. Y l l There are many advantages to the particular construction oi' steam motor which I have disclosed. 'I'he valves are arranged so that the steam travels always in one direction therethrough, thus eliminating successive changes in their temperature due tohot, high pressure steam passing'one way through them and then cooled, low pressure steam passing the other 1 way through the same valve.

l All pressure of steam tending to move the valve is eliminated from it by providing the piston 52 of substantially the same area as the top of the valve head 48 and the piston 54 of substantially the' same area as the bottom of the valve head. By this arrangement, the spring 5I is the.` only factor tending to move the valve stem 45 toward the cam 58. However, if it is found desirable to aid or eliminate the spring,

.or to oppose it, the pistons 52 rand 54 can be designed accordingly. l d

By the use of the pistons 52 and 54 in the `cylinder 32, all packing to prevent leakage is eliminated. y l

My particular compounding arrangement perautomaticshifting of the transfer and d it can `be controlled from the lever-10. Ihave Y A A'-mits direct transfer of steam from the high pres.- surecylinderto the low pressure cylinder, the transfer v valvesA and' passages' being of adequate .dimensions for providingan unobstructed'pas- A.power shaft and providing the cranks I2 and I4 at one-hundred and eighty degrees to each other, .the power stroke of one low pressure piston is exerted on one' side of the power shaft, while the 5 's'age for thetransfer of the steam, throughwhich the steam can be transferred with extreme ease. A Another decided advantage of this type of 'construction in a compound Aengine makes it possible tol obtain`ahigh startingtorquefsuch as possible inordinary `types of steam engines only v.by the use of some simpling device 'to "admit .jst'eam tothe low Vpressure cylinders directly. In

' my construction, the equivalent for a simpling def-'vice ris possible by extending the trailing edges y'ofthe cam lobes 60 and 62 as illustrated in Figure Av5.a. The trailing ends are indicated at 60e and 62e. f f l l 4 In Figure 5, the cams 60 and 62, when adjusted for no cut-olf, raise the 'intake valves 48 and keep them open during .a' full half revolution. By the construction in Figurey 5A itjwill be noted that rthe cams are longer circumferentially than in Figure 5, however, whereby it is possiblev to adjust themv sothat they are kept open longer than ahalf revolution, or inv other words,until after the high pressure piston starts on its upstroke. As soonas it starts on its upstroke, howeverthe transfer valvey 48a is open so thatthe high pressure steam entering the high pressure cylinder is transferred-to the low pressure cylinder. This `permits steam at boilerpressure to charge the low pressure cylinders Vwherein they act on the greater areas ofthe low pressure pistons and then ythus start a much heavier load than when the camv sleeve 58 is adjusted for ordinary operation and consequently cut off before the high pressure piston reaches its lower dead center. The relative motion of each high pressure piston'and itsr adjacent low pressure piston is illus- 40 trated dlagrammatically in Figure 2. It will be noted thatpractically all high pressure. pistons are at the opposite ends of their strokes with respect to the strokes of the low pressure pistons.

This is quite important toprovide a balanced running. motor, Ayetfa simple crank shaft with but two cranks isv necessary regardless of the number of cylinders used. t I V Even when the intake valve cam is adjusted for early cutoii',the motor operates smoothly because the low pressure pistons'have the Vexpansivepressure of the low pressure vsteam exerted on them during a full half revolutionof the power shaft.- Since Ithere are four cylinders, the

by forty-five degrees, thus insuring a very powerful but smooth rotation of the powerv shaft.

Even with only three cylinders, there would be a thirty degree overlap of the power impulses.

v.The admission periods of the high pressure steam rto the high pressure cylinders overlap whenever cut-off occurs later than one half the vdown stroke of the hi h pressurepiston. Forv any adjustl ment ofA earlier cut-off, the steam, being expansible, continues to exertV power on the high pressure pistons even though the highpressure steam intaker periods-do not overlap.

i1 The; result in such construction is a turbinelike actionl on the power shaft which can be attained only by my method of compounding and the radial arrangement of the cylinders with respect to the power shaft. This construction enables the operator to throttle down the motor to a. much smaller consumption of steam and a lfurther use of its expansible qualities without manner.

'escape powerstrokes of the low pressurepistons overlap undesirable pulsations or jerking effects `experiy Aenced with steam engines having slide valves By arranging the cylinders radially around the power stroke of the opposite low pressure cylinder is exerted on 4the other vside of the ,power shaft.` This-.gives a balancing eiect which cannot be attained by anyv arrangement of cylinders in alignment. Such construction gives to the A`power shaft a rolling action from all sides, minimirzing pressure on the bearings and consequent 'frictional losses which waste useful power.

For economys sake, the cylinders and valves should be covered with insulation to prevent the of heat. 'This, however, is not shown on the drawings and considerable condensationof the'parts to form a compact ,motor can also be .'made, the patent drawingsbeing only for the purpose of illustration.

Changes in the cam arrangement andthe method of controlling them, such'as illustrated by way of example on the drawings, and other changes may be made without departing from thereal spirit and purpose of my invention, and

' it is my intention to'cover by my claims, any

modified forms of structure or use of mechanical equivalents, which may be reasonably included within their scope. Y

l2 claim as my invention:

1. An expansible fluid pressure motor comprising a power shaft, a plurality of high pressure cylinders arranged radially therearound, a high pressure piston in each of said high pressure cylinders and operatively connected with said power shaft, a low pressure cylinder adjacent each high pressure cylinder,'a low pressure piston in each low pressure cylinder and operatively connected with said power shaft to move in a direction opposite its adjacent high pressure piston, means Vfor admitting lluid pressure to said high pressure cylinders successively and means for transferring fluid pressure from each of said high pressure cylinders intoits adjacent low pressure cylinder on Vthe upstroke of the high pressure piston therein,

said high pressure piston being of heavier material than said low pressure piston but bothof thembeing of substantially the same weight to balance each other.

2. An expansible fluid pressure motor comprising a power shaft, a plurality of high pressure cylinders arranged radially, therearound, a high pressure piston in each of said high pressure cylinders and operatively connected with'said power shaft, a low pressure cylinder adjacent each high pressure cylinder, a low pressure piston in each low pressure lcylinder and operatively connected with said power shaft to move in a direction opposite its adjacent high pressure piston, means for admitting fluid pressure to said high pressure cylinders successively during their downstrokes and for a part each of their upstrokes and means for transferring fluid pressure from each of said high pressure cylinders into its Aadjacent low pressure cylinder beginning at the .startof the upstroke of the high pressure piston.

3. An expansible iluid pressure motor comprising a-.power.shaft, a plurality of high pressure cylinders arranged radially therearound, a high pressure piston in each of said high pressure cylinders and operatively connected with said power shaft, a low pressure cylinder adjacent tively connected with said power shaft to move in a direction opposite its adjacent high pressure piston, said high pressure piston being of heavier material than Asaid low pressure piston but both of them being of substantially the same weight to balance each other.

4. An expansible fluid pressure motor comprising a power shaft, a `high pressure cylinder, a

' high pressure piston therein operatively connected-with said power shaft, a low pressure cylinder,

a low pressure piston thereinoperatively connected with said power shaft tomove in a direction'opposite said high pressure piston, means for admitting uid pressure to "said high pressure cylinder during` the downstroke o f the piston therein and for a part of the upstroke of said high pressure piston and means for transferring uid pressure from said high pressure cylinder into said low pressure cylinder beginning at the start oi' the upstroke of the high pressure piston.

y `5. An expansible fluid pressure motor comprising a power shaft. a high pressure cylinder, a

, high prssure piston therein and operativelxeconnected with said power shaft. a low prsure cylinder and a low pressure piston therein and operatively connected with said power shaft to move in a direction opposite said high pressure piston. said high pressure piston being of material having a greater specic gravity than the specinc gravity of` the material of said low pressure piston, but both of them Vbeing -of .A substantially the same weight l'to balance eachother.

` CARL'EMMIT BIBHXOP. 

